"We're always looking to improve the team and the squad," Solskjaer replied in response to the centre-back issue.
"I think we've been very, very solid at the back. Sometimes you might be exposed [when a player gets] in behind when you're pressing as high as we have done. We decided we're going to be a high pressing time when we can and if you don't take risks you won't improve.
"Once in a while we've been found some space behind us but I've not been concerned about it, no."